Rule 86A credit blocking procedure set for suspected ineligible input tax credit and non-existent firms Blocking and unblocking of input tax credit under Rule 86A is prescribed for cases involving invoices or other documents issued by non-existent firms or other specified indicators of fraudulent or ineligible credit. The circular authorises designated Deputy Commissioners and Assistant Commissioners to act within their territorial jurisdiction, requires inter-office requests and communication by e-mail, and limits action to the conditions expressly stated in Rule 86A(1). Action is to be completed within prescribed working timelines, communicated to the registered person, and recorded with reasons; cases not fit for action are to be returned with reasons and evidence.